La-related proteins (LaRPs) are RNA-binding proteins (RBPs) that contain a La-type helix-turn-helix (HTH) domain and are found in all eukaryotes, including plants, animals, and yeasts. Although the functions of a few LaRPs have been determined during plant growth and development, the roles of most LaRPs in plants remain unknown. Here, the function of an Arabidopsis thaliana LaRP6a (At5g46250) harboring a La-type HTH domain and an RNA-recognition motif was determined in the growth and development of Arabidopsis. Confocal analysis of subcellular localization of the LaRP6a–GFP fusion protein revealed that LaRP6a protein is localized to both the nucleus and plasma membrane. Overexpression of LaRP6a resulted in delayed flowering and increased plant height and seed yield. The transcript level of the floral repressor FLC was markedly increased in LaRP6a-overexpressing transgenic plants. LaRP6a protein bound to the 3ʹUTR of the FLC transcript and possessed RNA chaperone activity. Collectively, these results suggest that LaRP6a plays a role in the control of flowering time by regulating FLC transcript levels.

La相关蛋白（LaRP）是RNA结合蛋白（RBP），其中包含La型螺旋-螺旋-螺旋（HTH）域，存在于所有真核生物中，包括植物，动物和酵母菌。尽管在植物生长和发育过程中已经确定了一些LaRP的功能，但是大多数LaRP在植物中的作用仍然未知。在此，一个功能拟南芥LaRP6a（At5g46250）窝藏的La型HTH结构域和RNA-识别基序在的生长和发育，确定拟南芥。LaRP6a-GFP融合蛋白亚细胞定位的共聚焦分析表明，LaRP6a蛋白既定位于细胞核，又定位于质膜。LaRP6a的过表达导致开花延迟，植物高度和种子产量增加。在过表达LaRP6a的转基因植物中，阻花蛋白FLC的转录水平显着增加。LaRP6a蛋白与FLC转录本的3ʹUTR结合，并具有RNA伴侣活性。总的来说，这些结果表明LaRP6a通过调节FLC转录水平在开花时间的控制中发挥作用。